1. Technical Field
The present invention relates to an image-forming material.
2. Related Art
In recent years, a technology has attracted attention in which invisible information, which is not visible under normal visual conditions, is recorded on a document. The technology is useful in the security management and in embedding of Internet information or voice, and is able to enhance the added value of the document.
The invisible information may be recorded by a method in which an image-forming material having absorption in a near-infrared region of from 750 nm to 1000 nm—a wavelength region able to be detected by, for example, a silicon light-receiving device (such as CCD) but unable to be detected by human eyes—is used.